Vehicles, in particular cars or trucks for road traffic, are increasingly equipped with driver assistance systems that allow for the vehicle to be driven automatically in road traffic, which often is referred to as autonomous driving. This is enabled through the use of remote sensors arranged to acquire vehicle surrounding information to allow control of steering, and/or control of velocity on the basis thereof. During autonomous driving, an occupant of the vehicle is able to devote himself at least partially to other activities. However, no autonomous vehicle control arrangements are available today which are fully capable of performing autonomous driving in all situations, and at all road sections. Therefore, when the autonomous vehicle control arrangement recognizes an upcoming road section where the arrangement will likely become at least partially unable to perform the autonomous driving, the arrangement asks the occupant to take over control of the vehicle.
Attempts have been made to provide a driver assistance system that is able to output information in order to return the responsibility for driving to an occupant at the end of a roadway section drivable by an autopilot function. For example, the document US2015094899A1 relates to a driver assistance system of a vehicle where the driver assistance system is able to control the vehicle at least partially automatically, a method alerts the driver to retake control of the vehicle from the driver assistance system based on the distance between the current location of the vehicle and an end of the autopilot capable route section. An end of an autopilot route section in a route planned for the vehicle is determined and distance information is determined between a current position of the vehicle and the end of the autopilot route section. The distance information is compared to a first and a second threshold value, and a first or a second indication is output as a function thereof.
The taking over of control of the vehicle is often referred to as a handover. For safety reasons, such a handover may be performed prior to reaching an upcoming road section at which the autonomous vehicle control arrangement is likely to become at least partially unable to perform the autonomous driving of the vehicle. Since the occupant of the vehicle may be engaged with other activities than focusing on the road, a handover notification may be provided sufficiently early to allow the occupant to have sufficient time to prepare for manual driving of the vehicle. Still, if the handover notification is provided too early, it may distract and annoy the occupant, which may lead to an impaired trust and confidence of the handover notification. An occupant may, as a result thereof, return to the other activities. Thus, from a safety perspective, it may be desired to provide the handover notification at an appropriate time prior to reaching the upcoming road section. However, in some driving situations, it is difficult to predict the time available for autonomous driving, due to unpredictability of the traffic flow up to the upcoming road section.
In view of the above, there is a need for an arrangement capable of providing an improved handover notification.